Plug switch



Sept. 4, 1923.

B. RAETTIG PLUG SWITCH Filed Dec. 27, 1922 2 Sheets-Sheet l Fig.

l /n vento/1: .C 55E Fig.

sept. 4, 1923.

B. RAETTIG PLUG SWITCH Filed Deo. 27. 1922 2 Sheets-Sheet 2 as Vw,

Fig. 8

Patented Sept. 4, 1923. Y

UNITED STATES BRUNO RAETTIG, 0F HOFFNUNGSTHAL, NEAR COLOGNE,v GERMANY.

PLUG SWITCH.

Application filed December 27, 1922. Serial No. 609,355.

To all lwhom it may concern.'

Be it known, that I, BRUNO RAE'rfrrG, a citizen of the German Republic,residing at Hoifnungsthal, near Cologne, Germany, have invented certainnew and useful Improvements in Plug Switches, of which the following isa specification.

This invention relates to a plug switch in which the one contact part4is an oscillating switch member.

The known devices of this type are of very complicated construction;they require rather large openings in the casing whereby the water anddust tightness of the casing is impaired. The manipulation of the knowndevices is difficult, specially with the large sized devices. As in thedevices of known construction the hand of the operator remains incontact with the plug and the succession. of the insertion of plug andswitching in is not all ensured, the operator is not absolutelyprotected from electric shocks.. i

The invention has for its object to obviate these inconveniences.

According to the invention the plug which carries the second contactpart has slits for the reception of the oscillating switch meinber,which may be made of several parts for instance of several knifeswitches and which in the working position of the plug, is hidden andcovered in the box. In the switching off position it has been swun backinto the box casing so that it is wel protected against accidentalcontact. l

In order to increase the security against accidental contact of currentconducting parts the oscillating switch memberis preferably bent inangle shape, especially in U- shape towards its fulcrum.

The oscillating-switch member can be connected with a cam disk, the camsof which serve, the one for securing in the switch in position when theplug is inits inserted position, and the other for'the locking of thedevice if the plug is withdrawn.

The locking of the plug in the inserted position is preferably effectedby a pusher pressed against the lid by means of the cam so that a noseof the lid is held in engagement with a nose of the plug. A bolt canserve for locking the switch; this bolt engages with a oove arranged inthe wall which surroun s the plug hole. The bolt is oscillated at .theinsertion of the plug by the action of a lateral projection of this plugagainst the action of a spring so that it moves out of the path of theswitch cam and so that the bolt releases the cam if the plug isinserted, the operation of the switch being thus possible. If the plugis withdrawn the bolt prevents the operation of the switch. In thismanner the switching-in is prevented if the plug is withdrawn and thewithdrawal of the plug at the switched in position of the switch isprevented whereby the safety of the device is considerably increased.

On the drawing several forms of construc.

ing the withdrawal of the plug if the switchv is switched in and theswitching-in of the' switch if the plug is withdrawn.

Fig. 7 shows in end elevation the plug used in the form of constructionFig. 6.

Fig. 8 shows a longitudinal section through a part of the device on alarger scale and it illustrates the arrangement of the locking bolt usedin the device shown in Fig. 6 together with the cam of the switch.

Fig. 9 is a cross section perpendicular to Fig. 8. In the Figs. 8 and 9the locking bolt is in the locking position. v l

Fig. l() is a section similar to Fig. 9, the bolt being shown in thereleasing position.

Figs. 11 and 12 are elevations corresponding to Figs. 9 and 10respectively.

In the form of construction shown in Figs. 1 and 2 the switch knife aand the contact spring b which serves at the saine time as pivot axlefor the switchl knife are arranged upon an` insulated base plate c ofthe casing d ofthe switch box. The corresponding contact spring e of theswitch is arranged upon the insulation f for the plug in the plug casingg..

The switch knife a is operated in the well known manner by a lever 7Lupon the outer side of the casing. A bow i connected with the lever h,gets in the switching-in position in front of the opening of the box andprevents thus the insertion of the plug g or, the plug g being inserted,the withdrawal of the saine.

lf the plug g has to be withdrawn the lever it has to be brought to theposition indicated by dashand dot lines. The bow v'. is oscillated also90 and the switch knife a is brought out of engagement with the contactsprings e. At the switching-off movement the switch knife a moves out ofthe plug insulator through the slot lc.

`When the switch has been brought into a switching off position the plugg may be pulled out of casing d.

The plug insulation f is box-shaped so that the contacts e are protectedby said insulation. The number of the plug contacts e, of the knives aand of the slots 7c corresponds with the number of poles of the switch.A

At the bottom end of the opening of casing g for the insertion of theplug a plate Z with slots m is arranged which protects the parts in thecasing.

In the form of construction Fig. 3 the switch knife a is bent in U-shapeand mounted between the contact springs b by the end of one of -itsarms. The contact springs are thus situated above the Contact springs ofthe inserted plug.

Upon the pivot axle of the switch knives the bows n are pivotallymounted which are connected the one with the other by the insulatingplate 0. The switch knives a are connected with the bows n by springsnot shown on the drawing, Upon the pivot axle of the switch knives a andof the bows n there is further arranged a lever p which is rigidly fixedupon the pivot axle. The end of the lever is fork-shaped-and embracesthe end of rail -mounted upon the insulating plate 0. If lever p isoscillated by the aid of the switch lever arranged upon the outer sideof the casing d, it draws first along the bows and, as soon as thesprings arranged between the bows n and theswitch knives a aresufficiently tensioned the switch knives a will be pulled out frombetween the contact springs e.

The insulating plate Z obturates in this case the plug space of thecasing d with the exception of the small slots m arranged in theinsulating plate which permit the passage of the switch knives throughthe plate l. The switch knives a get, owing to their U-shape and thespecial mounting complete- 1y out of the range of the slots m, theystand above these slots so that even an intentional touching of thecurrent conducting switch knives through the slots m is prevented. Owingto the narrowness 0f the slots the interior of the casing is betterprotected against dust and other im urities than in the?1 form ofconstruction s own in Figs. 1 an 2.

In the second form of construction the plug insulation is perfectlyprotected by the plug mantle whilst it projects at the top from the plugmantle in the form of construction shown in Figs. 1 and 2.

The form of construction shown in Figs. 4 and 5 will be usedparticularly if instantaneous switching is not required which is thecase with arrangements limited by space, for instance in line couplings.

In this form of construction the switching in and out of the plugcontacts is effected by the forward and backward movement oi the switchknives a. is effected by sliding contacts r.

ln the form of construction shown in Figs. 6-12 the casing d is composedof the bottom part 1 and of the top part 2. In the Vremovable top part 2all the operative parts are arranged. The bottom part 1 comprises` onlyan insulating-partition 3 designed to prevent a contact of the ends ofthe leads with the current carrying parts.

Upon the axle 4 the switch knives a are pivot-ally mounted in a similarmanner as in Fig. 3.- The current is led in by springs b. Springs 5connect the switch knives a with the bows n, these latter beingconnected with one another by the insulating plate o. Upon this platethe catch rail g is fixed the end of which is embraced by thefork-shaped end of lever p which is rigidly connected with the axle 4.

This axle 4 carries further the switch lever h and a cam disk 6 which asshown in the drawing is made in one piece with the forkshaped lever p.The cam disk 6 has a cam 7 which, when the switch is being brought tothe switching in position, acts upon a pin 8 movably arranged in part 2of the casing so that the end of this pin 8 projects from the casingandl acts upon the nose g of lid 10 which covers the inlet opening ofthe switch if the plug is withdrawn.

The lid 10 is ressed downward so that the nose 11 of t e lid cannot beremoved from the path of nose 12 of plug g even by an upwardly directedpressure -upon the lid. The inserted plug is consequently securedagainst withdrawal.

A second cam 13 o cam disk 6 co-operates with a bolt 14 which ispivotally mounted upon the bolt 16 but acted upon b a torsion spring15.. An extension 17 of t e bolt enages with a groove 18 which isarranged 1n the wall of the plug hole of the casing.

As long as the bolt is in the position shown in Figs. 9 and 11 the bolt14 obstructs the path of cam 13 so that the switch cannot be turned.

The plug g has a laterally projecting nose 19 which is guided in thegroove 18 of the insertion of the plug. In the end position o' the plugthe nose 19 pushes the extension 17 of bolt 14 out of the groove andmakes The current carrying the bolt 14 oscillate from the position Figs.9 and 11 into the position Figs. 10 and 12, so that the cam 13 canfreely pass along the bolt 14 so that the `switch knives can beoscillated.

When the plug g is be-ing withdrawn from the switch the torsion spring15 brings the bolt 14 back to the position shown in Fig.- 9 so that theswitch is secured in the switching od position. The operation of thestructure illustrated in Figs. 6 to 12 inclusive may be briey-describedas follows When the plug g has been inserted and the lever h moved toswitching position the cam disc 6 will be swung about its pivot to causethe cam surface 7 to displace the pin 8 in an outward directionwhereupon it engages the nose 9 formed on the lid 10. Obviously, thislid has been previously raised to permit the insertion of the plug g.The pressure of the pin 8 upon-the nose 9 causes the nose 11 of thecover 10 to engage the nose 12 formed on the plug g and maintains thenose 11 in the path of the nose 12 to prevent the withdrawal of the plugg while the switch lever it is in its on position.

A projection 17 on a rotatably mounted bolt 14 is adapted to extend intoa groove 18 arranged in the wall of the casing through which the plug gis inserted. The plug g is provided with a nose 19 which, upon theinsertion of the plug is adapted to engage the extension 17 of the bolts14 and to rotatethe same against the action of a spring 15, thus movingthe bolt 14 outof the path of a cam 13 formed on the cam disc 16.Obviously before the plug g has been inserted to remove the bolt 14 fromthe path of the cam 13, the switch lever k cannot be moved in theswitching position. Therefore the switch is secured in oil positionuntil the insertion of the plug g.

1. An improved plug switch in which the alive contact member isconstructed as an oscillatable switch member comprising in combination,a box, an angularly shaped switch member oscillatably mounted in saidbox, the box being formed with slots through which said switch memberpasses from the off into the on "position, said angular 4 switch memberbeing moved in the off position away from said slots and a plug carrying`another contact part adapted to engage with said switch member.

2. An improved plug switch in which the alive contact member isconstructed as an oscillatable switch member comprising in combination aswitch box, a switch member oscillatably mounted in said box in aInanner to be protected therein in the off position, a plug, anotherycontact part upon said plug adapted to engage directly with saidoscillatable switch member, means for locking the plug in its insertedposition when the switch is in on7 position and separate means includinga. rotatablebolt for locking the switch in oi' position if the plug iswithdrawn.

3. An improved plug switch in which the alive contact member isconstructed as an oscillating switch member comprising in combination aswitch box, the switch member oscillatively mounted in said box in amanner that it is protested therein inthe olf position, a plug, anothercontact part upon said plug, a switch lever pivotally mounted in saidswitch box, a cam disk upon the inner end of the said switch lever, twocams on said disk, means cooperating with one of said cams for lockingthe plug in the inserted position, and a separate locking boltcontrolled by said plug and cooperatingwith the other cam if the plug iswithdrawn, for

locking said lever.

4. An improved plug switch in which the al-ive contact member isconstructed as an oscillating switch member comprising in combination aswitch box, the switch member oscillatively mounted in said box in amanner that it is protected therein in the off position, a plug, anothercontact part upon said plug, a nose laterally projecting from said plug,a switch lever pivotally mounted in said switch box, a cam disk upon theinner end of said switch lever, two cams of said disk on which one isdesigned to lock the plug in the inserted position, an abutment face onthe lid of the switch box, a nose on said lid, a pin movably arranged inthe switch box and adapted to be pressed against said abutment face bythe action of said other cam of the cam disk so that said nose of thelid engages with the nose of the plug.

5. An improved plug switch in which'the alive contact member isconstructed like an oscillatin switch member comprising in combination aswitch box, the switch member oscillatively mounted in said box in amaiiner that it is protected therein in the off position, a plug,another contact part upon said plug, a switch lever pivotally mounted insaid switch box, a cam disk upon the inner end of said switch lever, twocams of said disk on which one is designed to lock the plug in theinserted position, a cylindrical guide for the plug in said switch boxhaving a guide roove in its wall, a locking bolt located in the switchbox so that it projects into said guide groove, a spring'which holdssaid locking bolt into the path of said other cam and 4a lateralextension of the plug designed to act upon the inner end of said lockingbolt to swing the same, against the action of said spring, out of thepath of said cam.

The foregoing specification signed at Cologne, Germany, this'24th day ofNovem-

